Spring-frame for motor-cycles.



F. MACKEY.

PatentedJune 8, 1915.

2 SHEETS-SHEET l.

F. MACKEY.

SPRING FRAME FOR MOTOR CYCLES.

APPLICATlON FILED APR. 25, 1912'.

1,142,344. Patented June 8, 1915.

2 SHEETS-SHEET 2.

FRANK M AcKEY, or NEWARK, OHIO.

SPRfNG-FRAME r012. MOTOR-CYCLES.

Specification of Letters Patent.

Patented June 8, 1915.

Application filed April 25, 1912. Serial No. 693,239.

' torcycle which is calculated to give vary mg spring actions and resistances dependent upon the conditions under which the vehicle is running. In-other words, it relates to theprovision of a rear wheel structure for motorcycles which is calculated to.

automatically varythe resistanceconditions, this being primarily eflected by the provision of a spring element which is ca-- pable of. constantly changing its bearing pointand therebychanging the degree of, resistance oflered. In the preferred embodiment of this idea, I utilize a rigid rear fork structure and a floating fork structure, whichv floating fork structure is designed to carry the wheel and is designed to resist pressure upon the same by a spring element mounted upon the framework of the machine and having a variant arcuate resistance, being preferably rigidly mounted at one end and beingconnected at the other end to the floating fork in av manner to govern the yielding action thereof. 7

My invention further contemplates the provision of a means for preventing rattling of the framework due to this automatic adjustment.

My invention further aims to provide a meansfor readilyadapting the motorcycle structure to use as a tandem, by the pro- I vision of a supplemental seat upon the rear of the vehicle and by the conjunctive provision of a tubular reslstance element to behereinafter described. 1 7

Furthermore, my invention contemplates .a means for adjusting the tautness of the driving chain, while at the same t1me main 7 taining a constant line of transmission.

The preferred embodiment, of my inven tion is shown in the accompanying drawings, in which similar characters of reference designatecorresponding parts,.and in which: 1 c Figure 1 is a side elevation of the rear wheel structure of a motorcycle fitted with on line 2-2 of Fig. 1, Fig. 3 is a section taken on line 3-3 of Fig. 1, Fig. 4 is a detail view of the guideway serving as an adjusting anti-rattler for thefloating fork,

, my improvement, Fig. 2 is a section taken Fig; 5 is a detail perspectiv f th rigid s and floating fork structure used by me, and, Fig. '6 is a detail partly in elevation and partly in' section, of a supplemental resistance element sometimes used by me.

I In the drawings, the motorcycle structure is shown as comprising an upright member 1 of the main frame, carrying a saddle post 2 and saddle 3. The spring construction proper is shown as comprising a rear fork l rigidly connected to the main frame structure and formed of converging bifurcated legs 5 and 6, thelegs upon each side 7 being connected together as at 6 where there are rigidly connected channel elements or slide members designated 7 and 8 respectively. It will be noted that the upright '1 is a permanent part of the motorcycle main 1 structure, one portion of the rigid fork structure extending rearwardly from the crank hanger 9 in theform ofa single red 5 and being divided as at 5 .to form a portion of this structure, and the other, member 6 of the rigid fork structure extending rearwardly. and downwardly from a point adjacent the saddle element 3 in theform of a bifurcation its entire,

length. The construction thus far described is similar in many respects to the ordinary motor or bicycle structure now in use.

.Extending rearwardly from the crank hanger 9 and disposed one upon either side thereof, are legs 10 and 11 of the floating ing pivotally. mounted about the crank hanger and being joined as at 12 for a purpose tofbe hereinafter described. The floating fork structure 12 is somewhat similar in shape to the rigid fork structure 4cv andis completed by the provision of down- 'wardly and rearwardly inclined members fork structure 12, such legslOand ll beas at'17 at a point somewhat spaced from the main frame structure and are, connected to the free end of a leaf spring 18 supported at its" opposite end from a strap 'or backing element. 19 rigidly mounted upon the mainframe structure and incasedyyithinw a casing 20. Thisfilsif ing 20 may be of' any suitableform for housing the spring 18, it being necessary 7 only that the spring be permitted sufficient play. ,Itwill be noted that the various,

leaves :ofthis spring are bolted together at their lower, end. and this bolt structure; is

accessible through an aperture in the housin-g!20,.

In the. operation: of the structure as thus' faridescribed, theifloating fork may swing aboutits pivot at the crank hanger 9, while its-rear extremity is slidingly housed withinthe slidewaysii'rand 8, the. upward. or down- Ward movement of. the floating fork being resisted 'by the" spring element 18. After-its upward movement, thefioating fork is pre-.

1 VGIltGCLfTOIIl {excessive rebound". downward by theij oining member 12,- whichlirnits the downward movement of the floating fork'byi contact with thexshort. single red 5 oflthe rigid fork structure, thus serlvingiasa buffer in addition to strengthening the structure by itsjoining ofthe'legs10- 11. The. slide members 18and14 carriedby the fl0at;-"

ing fork operate in the channel :members- 7 and;81 rigidly carried by the rigid fork struc- 'ture andg'z'relieve the strain put upon the pivotpoints of'thelegs 10 and'll due-to the tendency to. lateral movement of the rear wheel while in motion These fslide members and" guideways also serve thepurpose 3 of preventing rattling of the rear structure duerto thislateral movement and vibration. V 'Ehesc'rews 9 are used to-d-raw up the-split portions of the ends of the rearwardly-ex- (tendinglegs 10 andill where they embrace i *the cra'nk hanger 9to form their pivotal' legs; I V a *L'T he 'springfelement 18 iis'peculiarly de-- signed.sothaupressure upon" the same varies its ib'earingpoint and consequently varies connections and in this manner means are provided for regulating the freedom of mov'enient' ab'out the pivot point ofthese the effective length of the, spring; Thus,- when agreater weightis applied to the spring, acertain portion thereof comesin'to' contactw ith the supporting strap19 and shortens thespring, thus giving it agreater resistance" capacity. The complete forcing ofgthe spring forwardlyis guarded'against j 'byftheiprovision 'of a resilient buffer element 22jwhich is in a position to receive 'the' fre c extrernity 'of the" spring ,element' V p rigid fork of thef-rame-may-be provided with a luggage carrier element '23 rigidly connected thereto'at 2 l and havinga rigid brace-25. In conjunction with thiselement, I may utilize detachable supplemental; resistance structure comprising a plunger 2'Z operating4within a casing 29 carried by the member 28 and provided wit-h a resistancec'oiled spring 27. The sections 27 and '28 are detachably secured as at 30 and 31. tothe luggage carrier and the float 'i ng fork respectively. It is of importance to provide a means for applying an additional spring for the reason thatthe placing of luggage or theseatingfof an additional personupon this luggage carrier, would otherwise render the spring 18 practically I inoperative by forcing it into continued contact with. the buffer 22. However, by

the provision. of this additional spring elenent,f-tl1e 7 spring 18 is supplemented and p there results ample resistance to the'weig'ht of both ridenand'luggage or of both riders.

It willsbe understoodfthatfthe leaf spring 18 is 'designedto' cushion therear wheel for one rid'er only and: if it isdesired' to place additional weight upon this Wheel',-the1 suppleme'ntal resistance element; is attached, it

being understood that it is'reinovedfrom operation jwhen; the motorcycle is carrying only one person. Th s supplemental resist- Y mice element having itsfspring normally 1 under tension acts betweenrth-e rigid fork structure and -the floating fork? structure 1 throughthe medium of; the luggage carrier and initial tension iscaIculated' to be sufficient to approximately counterbalance the weight ofanaclditionalpassenger or' compensate for one person only.

to he si multaneously. adjusted." They are helctinitheir adjusted position by set screws el -and 12,- the set screw tlldesirably oper-ft ating in a-groove f4c3;in"the inner eccentric i and} thereby preventingham-1 movement thereof. 7 Lateral movement of the; outer eccentric is of course prevented by the slot 4A through which; the set screw 4:2 passes-i 'It' will beunder'stood that the'transmissi'on r as desired, by moving the comparatively i elementmay lee readily tightened-tor loosenedff large portion er? one of the eccentrics rear; f Wardl y and by compensating fontheverti cal movement' by aolJustment of the. other eccentric. In other words, rotationofth'e innereccentric to bring the enlarged'portion thereoftoward the rear, would raise-the line of transmission andto compensate for this it I wouldbenecessary to shift the outer eccentric so as to permit the l1ne=of transmission to rema nnormal. Byoperatingthese eccentrics together, I am enabled? to obtain a, three- 1 quarters of; an inch'adj u'stment with an un changed" line of transmission, the aim of 7 which will be apparent. This maintenance of the unchangeddi'ne of translnission, is-of utmost importance particularly in the, utilization of a chain drive for the motorcycle. .VVhenever a floating forkstructure-is used,

there is tendency of the vehicle wheelto move up and down and 111-,S11Ch upward and transmission, such constant change .ofposi:

tion .of the line ofv drive must inevitably stretch the belt. If a chain .is used, it is practically impossible to preclude breaking of the chain unless the chain be maintained so loose as to create a liability'for the chain to come off. With my double eccentric adjustment, I am able to always'maintain the proper degree 'oftautnessifor'the chain.-

As is customary, I utilize a mud guardp which is secured as at 32. and 33 to the rigid fork structure, being further supported by braces 34 and 35 likewise connected to the rigid frame structure. Also, there is shown a support 36 which may be of any suitable type. p 1

In theproper embodiment of my lnvention, the rear wheel is capable-of an upward yielding movement and the resistance to this upward yielding movement is effected and measured by the relative curvature of the spring 18 and strap 19 in a manner which will be well understood.

What I claim, is:

1. A spring frame for motorcycles comprising a main frame, a rigid fork carried I by said frame, a V-shaped floating fork I her being pivotally supported by said main,

member, one pair of legs of said member being pivotally supported by said main frame, a resilient resistance element carried by said main frame and bearing on the ends of the other pair of legs of said V-shaped floating member, and guiding means carried by said forks for preventing lateral movement of the wheel carrying end of said floating fork independent of its pivotal connection.

2. A spring frame for motorcycles comprising a main frame, a rigid V-shaped fork carried by said frame, a V-shaped floating fork member, one pair of legs of said memframe, a resilient resistance element carried by said main frame and bearing on the ends of the other pair of legs of said V-shaped floating forked member, and guiding means carried by said forks for preventing lateral movement of the wheel carrying end of said floating fork independent of its pivotal connection.

3. A spring frame for motorcycles comprising a main frame, a. rigid fork forming a portion thereof, a floating fork pivoted to saidmain frame, a resilient resistance element operatively connected between said forks, U-shaped channel guide elements car- 1 said main frame,

ried by-one of said forks, and slide members slidably fitting between the legs of said guide elements and carried by the other of said forks, said guide elements and slide members being located at the opposite ends of said forks from the pivotal mounting of said floating fork to maintain a predeter- ,5.,A. spring frame for motorcycles comprising a main frame, a resiliently supported rear wheel, a luggage carrier attached-to said main. frame .over said rear wheel, and a supplemental detachable resistance element for use with said carrier and operatively connected between said main frame and said wheel.

6. A spring frame for motorcycles comprising a main frame, a floating fork, a resilient resistance element for said fork, a luggage carrier, and a supplemental resistance element for use with said carrier attached to said main frame over said floating fork and operatively connected between said main frame and said fork.

7. A spring frame for motorcycles, comprising a main frame, a rigid fork, a floating fork, a resilient resistance element for said floating fork, a luggage carrier attached to said main frame over said floating fork, and a supplemental detachable resistance element for use with said carrier and operatively connected between said forks.

8. A spring frame for motorcycles, comprising a main frame, a rigid fork, a floating fork, a resilient resistance element for said floating fork, a luggage carrier carried by said rigid fork over said floating fork, and a supplemental resistance element for use with said carrier operatively interposed between said rigid and floating forks.

9. A spring frame for motorcycles comprising a main frame, ing rigid fork forming a portion of said main frame, a rearwardly extending floating fork pivotally mounted onsaid main frame, and a resilient resistance element operatively being so formed that they engage each other on reverse or rebound movement of said floating fork before said resistance element has reached its limit of flexing.

10. A spring frame for motorcycles comprising a main frame, a rearwardly extending rigid fork forming a portion of a rearwardly extending floating fork pivotally mounted on said main frame, and a resilient resistance ele- 

